chore(ci): bump actions/checkout from 4 to 6

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
           - php: "8.2"
             deps: "lowest"
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up PHP
         uses: shivammathur/setup-php@v2
@@ -56,7 +56,7 @@ jobs:
     name: PHPStan
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: shivammathur/setup-php@v2
         with:
           php-version: "8.3"
@@ -69,7 +69,7 @@ jobs:
     name: Psalm
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: shivammathur/setup-php@v2
         with:
           php-version: "8.3"
@@ -82,7 +82,7 @@ jobs:
     name: php-cs-fixer
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: shivammathur/setup-php@v2
         with:
           php-version: "8.3"

.github/workflows/docs.yml

@@ -27,7 +27,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       # phpDocumentor publishes an official Docker image and a GitHub
       # Action — but the action only has versioned tags (no moving "v3"),